1. Field of the Invention
The present disclosure relates to a light emitting device and a method for producing a light emitting device.
2. Description of the Related Art
In recent years, general lighting devices are becoming more popular which include light emitting diodes (hereinafter also referred to as LEDs), which have low power consumption, instead of conventional filament lamps. The applications of LEDs broaden to a back light source, lighting, a vehicle light source, and the like. An example of such light emitting device 1000 includes LEDs 1001, which are installed on a lead frame 1022 as shown in a perspective view of FIG. 10. The lead frame 1022 is used for electrical connection to the outside. The lead frame 1022 is embedded in a resin package 1030 as shown in a cross-sectional view of FIG. 11.
In order to improve the durability of this type of light emitting device, the strength of the resin package is required to be higher. Also, since higher output power is required for this type of light emitting device in recent years, a number of LEDs are installed to increase its light amount. To address this, the light emitting device necessarily dissipates a larger amount of heat. In addition, power supplied to the light emitting device is increased for higher output power, while resistance to high pressure becomes important for the device. Additionally, it is required to prevent tarnishing of the Ag-plated lead frame caused by sulfuration, which is likely to occur with aging. See Japanese Laid-Open Patent Publication No. 2013-540,362 A, and Japanese Patent Laid-Open Publication No. JP 2006-093,738 A.